Not strictly solo I suppose, more just lack of help from outside sources. First few like what I was talking about above that jump to mind are these 2. video from Deadmen, video from Jon Conti

Some terrific examples that are hardly ever accidentally unprepared. The most obvious, Les Stroud. He’s got the full Survivorman Seasons 1-5, as well as most of the spin-offs they did with it (Survivorman for Kids, Survivorman & Son, etc) Alone Across the Arctic. Dude paddles (spoiler alert: it’s mostly pushing, rather than paddling) across Canada’s Arctic in one season. Really puts into perspective how much extra weight being properly prepared adds, and he gets resupplied a few times over the few months.